Preloader for gallery

Hey everybody,

I am using this XML gallery from kirupa

When i want to add a preloader the whol gallery stops working.
Anybody have a clue what this problem could be ?
I just want a simple movieclip with the word Loading to be flashing while it loads thats all but it just doesn’t work with any kind of preloader. Can somebody help me with a good description or maybe the actionscript or a source file for it.

Thanks in advance